When this 16-year-old woke up one morning her eyes were full of pus. You can find the cause in every pharmacy.

Sixteen-year-old Australian Tylah Durie is a pretty normal teenager, which means she cares about how she looks. She spends a certain amount of time in front of the mirror styling her hair and putting on makeup.

One day she had the idea to tint her eyebrows and eyelashes. She'd gotten hair and eyebrow coloring at the drugstore before so she didn't think there was the slightest risk.

That was quite a mistake.

Since minor procedures like this had always gone well, it didn't occur to her to check the exact ingredients. But unlike previous products she had purchased, this one had p-Phenylenediamine (often simply known as PPD). This chemical is often used instead of henna or other coloring agents.

Before you have contact with this chemical, it's hugely important to find out whether you're allergic to it by doing a quick patch test. Most people don't know if they can tolerate it or not, which can get you into a terrible situation like Tylah's.

The morning after her cosmetic adventure, Tylah woke up but couldn't open her eyes. Her allergic reaction to the product was so strong that her eyes were swollen shut. She realized pretty quickly that she had to go to the ER.

"I woke up almost blind because of the reaction, my eyes had blown up like huge balloons, I was crying and screaming. It was like having beach sand thrown in your eyeballs and not being able to get it out, then a stinging like razor blades on my eyebrows," she described later.

Doctors at the hospital soon confirmed that her fears were well-founded. "I have chemical burns on both my eyebrows and I couldn't see out of my eyes because of the swelling," she wrote at the time on social media to warn her friends, later also recalling that "I was terrified of losing my eyesight at such a young age. An optometrist the next day told me how lucky I was not to have gone blind."

In the end she was lucky. Thanks to quick intervention and a prescription ointment, she was able to make a full recovery. She did the world a service too, by sharing her grisly experience. Hopefully her story will serve as a warning to others.

Even if you've never been allergic to dyes, one new ingredient can cause "excruciating" pain. Tylah learned this lesson the hard way, but for the rest of us it's time to start doing patch tests before using any new cosmetic products! Much better to be safe than sorry.